Method and apparatus for anti-blocking hetnet deployment

Abstract

A new approach to anti-blocking cellularcommunication for HetNet deployment is proposed. First, a block detector sends a block indicator from an LPN to a scheduler in a macro base station. The scheduler then collects the block indicator statistics of each LPN on a sub-frame basis and updates the statistics in each sub-frame. If the statistics of received block indicators for one sub-frame during an observation period of a specific LPN exceeds a first predefined threshold, then the scheduler will not schedule any more uplink transmission to the LPN during the sub-frame for those UEs which are connected to the LPN. When the statistics of received block indicators becomes less than a second predefined threshold, which is less than the first threshold, the scheduler removes the limitation on uplink transmission to the LPN and allocates the sub-frame of the LPN as usual.

What is claimed is: 
     
         1 . A system to support anti-blocking cellular communication for heterogeneous network (HetNet) deployment, comprising:
 a scheduler in a base station, which in operation,
 accepts at the base station a block indicator from a low power node (LPN) within a coverage of the base station, wherein the block indicator indicates that a blocking situation at the LPN has been detected; 
 calculates block indicator statistics of the LPN for each sub-frame within an observation period at the base station; 
 allocates no uplink resources to a mobile device served by the LPN for uplink communication with the base station if the block indicator statistics of the LPN exceeds a first threshold during the subs-frame of the observation period. 
   
     
     
         2 . The system of  claim 1 , wherein:
 the scheduler controls and schedules transmission and retransmission of the uplink communication between the mobile device and the base station through the LPN.   
     
     
         3 . The system of  claim 2 , wherein:
 the scheduler utilizes the block indicator statistics in handling of the retransmission of the uplink communication that has been blocked at the LPN.   
     
     
         4 . The system of  claim 1 , wherein:
 the sub-frame is a contiguous number of time units of radio frequency (RF) resources within a frame that has the same direction property for uplink or downlink communication.   
     
     
         5 . The system of  claim 1 , wherein:
 the block indicator statistics is a counter of block indicators received for each sub-frame within the observation period.   
     
     
         6 . The system of  claim 1 , wherein:
 the scheduler updates the block indicator statistics based on the block indictors received for the sub-frame during the observation period.   
     
     
         7 . The system of  claim 1 , wherein:
 the scheduler tags the sub-frame as “un-schedulable” for the LPN if the block indicator statistics of the LPN exceeds the first threshold during the subs-frame of the observation period.   
     
     
         8 . The system of  claim 7 , wherein:
 the scheduler removes the “un-schedulable” tag on the sub-frame for the LPN if the block indicator statistics of the LPN becomes less than a second threshold that is less than the first threshold during the subs-frame of the observation period.   
     
     
         9 . The system of  claim 1 , wherein:
 the scheduler resumes to allocate uplink resources to the mobile device whose uplink communication is received by the LPN if the block indicator statistics of the LPN becomes less than a second threshold that is less than the first threshold during the subs-frame of the observation period.   
     
     
         10 . The system of  claim 1 , further comprising:
 a block detector in the LPN, which in operation,
 receives at the LPN an incoming waveform from the mobile device served by the LPN for uplink communication with the base station; 
 analyzes the incoming waveform to detect the blocking situation occurring at the LPN during a time period; 
 generates and provides the block indicator to the base station if the blocking situation is detected. 
   
     
     
         11 . The system of  claim 10 , wherein:
 the block detector detects whether the uplink communication received at the LPN is blocked due to high-power transmission by one or more nearby user equipment devices during the time period.   
     
     
         12 . The system of  claim 10 , wherein:
 the block detector analyzes the incoming waveform in analog form.   
     
     
         13 . The system of  claim 10 , wherein:
 the block detector analyzes the incoming waveform after the waveform is converted to a digital form.   
     
     
         14 . The system of  claim 10 , wherein:
 the block detector utilizes knowledge about time and frequency allocation of the uplink transmissions by the mobile device served by the LPN to detect the blocking situation.   
     
     
         15 . A method to support anti-blocking cellular communication for heterogeneous network (HetNet) deployment, comprising:
 accepting at a base station a block indicator from a low power node (LPN) within a coverage of the base station, wherein the block indicator indicates that a blocking situation at the LPN has been detected;   calculating block indicator statistics of the LPN for each sub-frame within an observation period at the base station;   allocating no uplink resources to a mobile device served by the LPN for uplink communication with the base station if the block indicator statistics of the LPN exceeds certain threshold during the subs-frame of the observation period.   
     
     
         16 . The method of  claim 15 , further comprising:
 controlling and scheduling transmission and retransmission of the uplink communication between the mobile device and the base station through the LPN.   
     
     
         17 . The method of  claim 15 , further comprising:
 utilizing the block indicator statistics in handling of the retransmission of the uplink communication that has been blocked at the LPN.   
     
     
         18 . The method of  claim 15 , further comprising:
 updating the block indicator statistics based on the block indictors received for the sub-frame during the observation period.   
     
     
         19 . The method of  claim 15 , further comprising:
 tagging the sub-frame as “un-schedulable” for the LPN if the block indicator statistics of the LPN exceeds the first threshold during the subs-frame of the observation period.   
     
     
         20 . The method of  claim 19 , further comprising:
 removing the “un-schedulable” tag on the sub-frame for the LPN if the block indicator statistics of the LPN becomes less than a second threshold that is less than the first threshold during the subs-frame of the observation period.   
     
     
         21 . The method of  claim 19 , further comprising:
 resuming to allocate uplink resources to the mobile device whose uplink communication is received by the LPN if the block indicator statistics of the LPN becomes less than a second threshold that is less than the first threshold during the subs-frame of the observation period.   
     
     
         22 . The method of  claim 15 , further comprising:
 receiving at the LPN an incoming waveform from the mobile device served by the LPN for uplink communication with the base station;   analyzing the incoming waveform to detect the blocking situation occurring at the LPN during a time period;   generating and providing the block indicator to the base station if the blocking situation is detected.   
     
     
         23 . The method of  claim 22 , further comprising:
 detecting whether the uplink communication received at the LPN is blocked due to high-power transmission by one or more nearby user equipment devices during the time period.   
     
     
         24 . The method of  claim 22 , further comprising:
 analyzing the incoming waveform in analog form.   
     
     
         25 . The method of  claim 22 , further comprising:
 analyzing the incoming waveform after the waveform is converted to a digital form.   
     
     
         26 . The method of  claim 22 , further comprising:
 utilizing knowledge about time and frequency allocation of the uplink transmissions by the mobile device served by the LPN to detect the blocking situation.